There has been known a vehicle seat to which an ISOFIX type child seat in accordance with ISOFIX, which is an international standard for installing a child seat, is capable of being attached. In such a vehicle seat, ISOFIX anchors, which are locking members to which a pair of left and right attaching members provided at a rear portion of the child seat are locked, are disposed in through holes provided at a rear end portion or the like of a seat cushion of the vehicle seat. Further, a cover member is provided so as to protect an outer peripheral edge portion of a front opening of the through hole and an outer peripheral wall portion of the through hole and to improve external appearance. In the vehicle seat described in JP-A-2001-354058, a cover member made of resin is attached to a seat pad on which a seat cover is stretched by engaging a part of the cover member with the ISOFIX anchor. Further, a lid member for opening and closing a front opening of the cover member is attached.
In the technology described in JP-A-2001-354058, the lid member is attached such that a flange portion of the cover member is covered from a front side. Meanwhile, in a case where there is a demand in design or a demand to minimize a portion protruding forward from the cover member, the lid member is disposed at an inner side of the flange portion of the cover member. In such a case, when it is intended to smoothly insert the pair of left and right attaching members provided at the rear portion of the child seat into the through holes without a risk of being caught by the flange portion of the cover member, an R-chamfered portion is preferably provided at an inner corner portion of the flange portion of the cover member. However, when the R-chamfered portion is provided, there is a problem that a gap between the inner side of the flange portion of the cover member and an outer peripheral edge portion of the lid member looks larger and the appearance design may be deteriorated.